The definition of vivid is something that is full of light color feelings or that can make you feel all this that even when it is not real you can almost touch it, then in the sentence when it says that his eyes were sparkled it means that they were so full of joy that they seem to bright and to project all of this emotions to others.
even though adverbs are more commonly thought of as words ending with -ing, they aren't always! "never" is an adverb that describes how often he misses chess club. how often? never!
